The present invention relates to a lock for a motor vehicle door, particularly to a lock which is automatically unlocked upon opening, and more specifically, to an electric lock providing assistance with opening and/or assistance with locking.
In electric locks with assistance with opening, the mechanism for opening the lock is driven by a geared motor unit, an electromagnetic system or any other equivalent device which is built into a sealed part of the lock casing, so that the electrical components and gears can be isolated from dust, water and any foreign body which could enter the lock, when the vehicle is in use. The electric mechanism for assisting with opening is generally operated via the exterior handles or paddles for opening the door, which are fitted with a contactor, sensor, microswitch or any other detector which is connected by an electric cable to the device for assisting with opening the lock, in order to transmit the command to open. Given that the exterior handles or paddles are exposed to adverse weather conditions, it is necessary to make the opening detectors, and their electric cables and connectors, completely sealed, and this increases the cost of the lock.
A first object of the invention is to provide an electric lock with assistance with opening which minimizes the electrical connections and the sealing constraints, in order to reduce the cost of the lock.
The second object of the present invention is to provide an electric lock with assistance with opening, the layout of the mechanisms of which is improved.
For safety reasons, locks for front doors and sometimes for rear doors are generally equipped with a mechanism for automatically unlocking on opening, when the user actuates the interior door handle. This is because, if a user is driving along in the locked position, for example, so that he or she runs no risk of being attacked when he or she stops at traffic lights, it is important that, in the event of an accident, he or she can easily get out of his or her vehicle without having first of all to unlock the door before being able to open it.
Another advantage is that the user, by actuating the interior door handle, is able, in a single action, both to unlock and to open the door, whereas it would be somewhat troublesome, for a user, to have to unlock the door before being able to open it.
Furthermore, in instances when the driver of the vehicle, having got out, closes the door again leaving the keys inside, he or she can go back into the vehicle because the door will have automatically unlocked upon opening, something which would not have been the case if it had been possible for the door to be opened from the inside without unlocking the lock.
However, this function of automatically unlocking upon opening, also known by the name of xe2x80x9coverridexe2x80x9d does consume energy, because the energy needed for unlocking is in addition to the energy required for opening the lock. This energy may be supplied via manual effort on the part of the user, in the case of an entirely mechanical lock, or by mechanisms providing electrical assistance with opening and unlocking, in the case of an electric lock.
The third object of the invention is to provide a lock with automatic unlocking on opening, which reduces the energy that has to be supplied in order to fulfill such a function.
Customarily, locks, both electric and mechanical, comprise a great many levers: a lever for opening from the outside, a lever for opening from the inside, a lever for locking from the inside, a lever for locking from the outside, and one or more intermediate levers. Furthermore, these levers are connected by linkage means, for example linkages, cables and cable sheaths, to operating means, such as the lock barrel and the interior and exterior handles or paddles.
The fourth object of the invention is to provide a simplified lock for a vehicle door, which minimizes the number of levers and linkage means for fulfilling the various functions of the lock.
In order to achieve the first aforementioned objective, the first subject of the invention is an electric lock for a motor vehicle door comprises a lock casing, of which a first compartment, known as the retention compartment, contains a latch capable of retaining a striker, and a pawl for locking the latch in the striker-retaining position, and of which a second compartment, known as the driveline transmission compartment, contains, in sealed manner, a mechanism for locking the lock, comprising a locking lever capable of placing the lock in the locked/unlocked position, and an opening mechanism comprising an electric motor for assisting with opening, capable of driving a lever for opening from the outside, so as to actuate the pawl into its position for releasing the latch, in response to a control signal for opening from the outside emitted by a contactor for opening from the outside, when an external operating means, such as an exterior door handle or paddle, is actuated by a user, characterized in that it comprises an outside mechanical linkage means, an outer portion of which is intended to be connected to the means for operating from the outside, and another, inner, portion of which extends into the sealed second compartment of the lock, the said contactor for opening from the outside being arranged in the said sealed second compartment on the path of the said inner portion of the outside mechanical linkage means, so as to emit an opening-from-the-outside control signal when the mechanical linkage means is moved over a determined opening travel when the means for operating from the outside is being actuated.
Thus, all the electrical connections between the exterior door handle and the lock are dispensed with, and it is no longer necessary to seal the contactor, because it is located in a compartment of the lock which is already sealed.
In a particular embodiment, the inner portion of the mechanical linkage means is secured to a slider which is guided by a slideway inside the sealed second compartment, along the opening travel of the mechanical linkage means, and which is capable of cooperating, at the end of opening travel, with the contactor to trigger the emission to the electric motor of the opening control signal.
Advantageously, the lock of the invention is associated with a so-called xe2x80x9chands freexe2x80x9d remote recognition system which is intended to supply power to the electric motor when an authorized user has been identified by the said recognition system, near to the vehicle. Such a recognition system is known per se and consists in providing a badge fitted with an emitter worn or carried by the user and a receiver implanted in the vehicle which controls the supply of electrical power to the vehicle when it receives an appropriate coded signal emitted by the badge. Thus, when the authorized user actuates the exterior door handle, opening is triggered automatically, without the lock having necessarily to have been unlocked beforehand. Specifically, the lock may be unlocked before, at the same time as, or after electrically controlled opening. Given that it is not necessary for the lock to be unlocked in order for the lock to be opened from the outside, opening may occur more quickly. The fact that prior unlocking of the lock is not necessary does not constitute a drawback, because the lock can be opened directly only if an authorized user has been identified by the recognition system, failing which the electric motor will not be powered, and opening will therefore be impossible.
Unlike known locks, in which action on the exterior handle first of all brings about unlocking then brings about opening, the lock of the invention has two parallel driveline transmission lines, one for electrical opening, the other for unlocking.
It will be noted that the opening travel of the linkage means for triggering electrical opening may be short, for example of the order of 5 mm.
According to another feature of the invention, the inner portion of the mechanical linkage means comprises, at its free end, an endpiece capable of causing an emergency opening lever to pivot, in the event of an electrical fault or in the event of the vehicle battery being flat, by moving the said linkage means, under the action of the means for operating from the outside, over an additional travel beyond the electrical opening travel, the said emergency lever being capable of moving, during the said additional travel, the lever for opening from the outside, so as to release the latch.
Advantageously, the emergency lever is subject to the action of a very stiff spring which returns it to its position of rest, which means that the user has to force the means for operating from the outside in order to actuate the emergency lever, so that the user will not needlessly actuate the emergency lever when electrical assistance with opening is working.
According to yet another feature, the locking lever is able, when the lock is locked, to place the aforementioned endpiece of the linking means in a position in which the endpiece escapes the action of the emergency lever, irrespective of the movement of the linkage means, and, when the lock is unlocked, to place the said endpiece in a position in which it cooperates with the emergency lever, during the additional travel.
Advantageously, the linking means is a flexible cable and the locking lever comprises an arm capable of moving the endpiece of the cable, to alter the path of the cable, so that the said endpiece escapes the action of the emergency lever when the lock is locked.
In a particular embodiment, the emergency lever comprises a fork, between the branches of which the linking cable passes, the separation of the branches being less than the size of the endpiece, so that the latter can drive the emergency lever, when the lock is in the unlocked position. In this case, the branches of the fork may, at their free end, have a guide ramp for guiding the endpiece along the path of the cable in its escaped position, when the cable is moved under the action of the means for operating from the outside.
According to yet another feature, the lock comprises a means of automatically unlocking on opening, comprising a first lever equipped with a cam follower element arranged in the first, retention, compartment for cooperating with a cam profile provided on the latch, and a second lever arranged in the sealed second compartment and capable of cooperating with a abutment provided on the locking lever so that as the latch rotates towards its open position, the cam profile causes a movement of the cam follower element and consequently of the second lever which rotates as one with the first lever, to automatically bring the locking lever into its unlocked position.
In this case, the second lever of the means of automatically unlocking on opening is capable, when the latch is in the open position, of immobilizing the abutment of the locking lever to prevent the lock from being locked in the door-open position.
To achieve the aforementioned second objective, the second subject of the invention is an electric lock for a motor vehicle door, comprising a lock casing, of which a first compartment, known as the retention compartment, contains a latch capable of retaining a striker and a pawl for immobilizing the latch in the striker-retaining position, and of which a second compartment, known as the driveline transmission compartment, contains, in sealed manner, a locking mechanism comprising a locking lever capable of placing the lock in a locked/unlocked position, and an opening mechanism comprising an electric motor for assisting with opening, characterized in that, in the second, driveline transmission, compartment, the electric motor is capable of rotating, via a set of gears, a gear wheel with at least one radially eccentric wrist pin, the said wrist pin being intended, as the wheel rotates, to drive an operating lever until a radially eccentric peg on the said wheel comes into contact with an elastic end-of-opening travel stop, the supply of electrical power to the motor being timed to last for long enough, for example 100 ms, for the said peg to be sure of reaching the elastic stop, the said operating lever rotating as one with an opening lever arranged in the first, retention, compartment and capable of cooperating with the pawl to move it into the position for releasing the latch.
In a particular embodiment, the set of gears comprises a first pinion secured to the drive shaft of the electric motor and meshing with a second pinion secured to a worm which meshes peripherally with the said gear wheel, the said worm being connected to a spiral return spring which is intended to make the worm rotate in the opposite direction when the power supply to the motor is cut, thus causing the wrist pin of the gear wheel to return to its initial position.
According to yet another feature of the invention, the locking mechanism comprises a reversible second electric motor for assisting with locking/unlocking the lock when central locking or unlocking is commanded from outside or inside, the drive shaft of the second electric motor being fitted with a pinion meshing with a toothed sector of the locking lever.
Advantageously, the electric motor for assisting with opening is intended to drive the opening lever in response to a control signal emitted by a contactor for opening from the outside, when an external operating means, such as an exterior door handle or paddle, is activated by a user.
In this case, the lock may comprise an outside mechanical linkage means, an outer portion of which is intended to be connected to the means for operating from the outside, and another, inner, portion of which extends into the sealed second compartment of the lock, the said contactor for opening from the outside being arranged in the said sealed second compartment on the path of the said inner portion of the outside mechanical linkage means, so as to emit an opening-from-the-outside control signal when the mechanical linkage means is moved over a determined opening travel when the means for operating from the outside is being actuated.
According to yet another feature, the pawl is connected to a means for operating from the inside, such as an interior door handle or paddle, by means of a mechanical linkage means such as a cable or linkage, to bring the pawl into a position for releasing the latch.
In a particular embodiment, the locking lever comprises three arms: a first arm for placing a mechanical means of linking to a means for operating from the outside in a locked or unlocked position; a second arm for possibly linking with a lock cylinder; and a third arm for possibly linking with a member for operating the door from the inside. This member for operating from the inside is intended to replace the lock stalk customarily used.
In an alternative embodiment, the opening mechanism comprises an emergency lever for mechanical opening in the event of an electrical fault or failure of the vehicle battery, this emergency lever comprising a first branch intended to cooperate with a peg projecting from the operating lever, and a second branch intended to cooperate with a mechanical means of linking to a means for operating from the outside, when the lock is in the unlocked position.
According to yet another feature of the invention, the lock comprises a means of automatically unlocking upon opening, comprising a first lever equipped with a cam follower element arranged in the first, retention, compartment to cooperate with a cam profile provided on the latch, and a second lever arranged in the sealed second compartment and capable of cooperating with a abutment provided on the locking lever, so that as the latch rotates into its open position, the cam profile causes a movement of the cam follower element and consequently of the second lever which rotates as one with the first lever, to automatically bring the locking lever into its unlocked position.
In this case, the second lever of the means of automatically unlocking on opening is capable, when the latch is in the open position, of immobilizing the abutment of the locking lever so as to prevent the lock from being locked in the door-open position.
To achieve the aforementioned third objective, the third subject of the invention is a lock for a motor vehicle door, comprising a latch capable of retaining a door striker, a pawl for immobilizing the latch in the striker-retaining position, an opening mechanism comprising at least one actuating means capable of cooperating with the pawl to bring it into a position for releasing the latch, under the action of a means for operating from the inside or the outside, and a locking mechanism comprising a locking lever for placing the lock in a locked or unlocked position, characterized in that it comprises a means for automatically unlocking upon opening comprising, on the one hand, a cam follower element cooperating with a cam profile provided on the latch and, on the other hand, a bearing portion capable of cooperating with a abutment provided on the locking lever so that as the latch rotates towards its open position, the cam profile causes a movement of the cam follower element and consequently of the said bearing portion so as to automatically bring the locking lever into its unlocked position. Thus, under the action of the means for operating from the inside or the outside, when the pawl releases the latch, the latter is driven into its open position, under the reaction force of the compressed door seal, which automatically causes the lock to unlock, without any unlocking force needing to be. provided. What actually happens is that when a door is closed, the seals are compressed and exert a reaction force of the order of 150 N to 500 N on the latch. In consequence, when the pawl releases the latch, the reaction force of the seal causes the latch to pivot, moving the door ajar and at the same time unlocking it. Use is thus made of the energy stored up in the door seals, which energy was not currently used for unlocking purposes.
Advantageously, in the latch-open position, the bearing portion of the means of automatically unlocking on opening immobilizes the abutment of the locking lever, and this prevents the lock from being locked in the door-open position.
In a particular embodiment, the means of automatically unlocking on opening comprises a first lever equipped with a cam follower peg cooperating with the cam profile of the latch, and a second lever which rotates as one with the first lever and is equipped with the said bearing portion capable of cooperating with a abutment peg on the locking lever.
Advantageously, the cam follower peg of the first lever is capable of cooperating with a door opening contactor at the end of rotational travel of the latch into its open position, the said door opening contactor intended to emit a signal corresponding to information that the door is open to a central processing unit so as to activate, in a way known per se, for example a light indicator on the vehicle dashboard or a lamp in the ceiling of the cabin.
Advantageously, the means of automatically unlocking on opening brings the locking lever into the unlocked position before the end of the opening travel of the latch.
In a particular embodiment, the locking mechanism comprises a reversible electric motor for driving the locking lever between its locked and unlocked positions when central-locking or central-unlocking is operated from the outside or from the inside.
Provision may also be made for the lock of the invention to be associated with an impact sensor so that when an impact is detected, a control signal is sent to the electric motor of the locking mechanism to drive the locking lever into its unlocked position. Thus, if, because of an impact, the door cannot open sufficiently, which means that the latch cannot rotate enough to actuate the means of automatically unlocking on opening, the lock will nonetheless be unlocked.
According to another feature, the aforementioned actuating means comprises a mechanical linkage means, such as a cable or linkage, connecting the pawl to a means for operating from the inside, for example an interior door handle or paddle.
According to yet another feature, the actuating means comprises a lever for opening from the outside, capable of cooperating with the pawl to bring it into the position for releasing the latch, the said lever for opening from the outside being able to be driven by an electric motor for assisting with opening, in response to a control signal emitted by a contactor for opening from the outside, when a means for operating from the outside is actuated by the user.
In this case, the lock may comprise an outside mechanical linkage means, an outer portion of which is intended to be connected to the means for operating from the outside, and another, inner, portion of which extends into the sealed second compartment of the lock, the said contactor for opening from the outside being arranged in the said sealed second compartment on the path of the said inner portion of the outside mechanical linkage means, so as to emit an opening-from-the-outside control signal when the mechanical linkage means is moved over a determined opening travel when the means for operating from the outside is being actuated.
To achieve the aforementioned fourth objective, the fourth subject of the invention is a lock for a motor vehicle door, comprising a latch capable of retaining a striker, a pawl for immobilizing the latch in the striker-retaining position, a mechanism for opening from the outside for actuating the pawl into its position for releasing the latch, an outside mechanical linkage means, an outer portion of which is intended to be connected to a means for operating from the outside, such as an exterior door handle or paddle, and an inner portion of which extends inside the lock casing and is capable of actuating the mechanism for opening from the outside, so as to open the lock, in response to actuation of the means for operating from the outside, and a locking mechanism comprising a bi-stable locking lever for placing the lock in a locked or unlocked position, characterized in that the locking lever is capable of altering the path of the inner portion of the mechanical linkage means so that when the lock is in the locked position, the said inner portion of the mechanical linkage means escapes the action of the mechanism for opening from the outside and so that when the lock is in the unlocked position, the inner portion of the mechanical linkage means is placed in a position in which it cooperates with the mechanism for opening from the outside.
Advantageously, the outside mechanical linkage means is a flexible cable comprising, at the free end of its inner portion, an endpiece which is able to be moved by an arm of the locking lever in a direction roughly perpendicular to the direction of travel of the cable. The mechanism for opening from the outside may comprise an actuating lever equipped, at one end, with a fork, between the branches of which the inner portion of the cable passes when the lock is in the unlocked position, the separation of the branches being less than the size of the said endpiece so that the latter can drive the said actuating lever, the inner portion of the cable and its endpiece escaping the action of the said fork when the lock is in the locked position. Thus, the inherent flexibility of the linking cable is used to disengage the link between the means for operating from the outside and the mechanism for opening from the outside, for locking the lock. When the locking lever is returned from its locked position to its unlocked position, the cable, because of its inherent elasticity, returns to its position in which it is engaged with the fork of the actuating lever.
In this case, the branches of the fork may, at their free end, comprise a guide ramp for guiding the endpiece of the cable into its escaped locking position when the cable is pulled under the action of the means for operating from the outside.
According to another feature, the lock comprises a means of automatically unlocking upon opening comprising, on the one hand, a cam follower element cooperating with a cam profile provided on the latch and, on the other hand, a bearing portion capable of cooperating with a abutment provided on the locking lever so that as the latch rotates into its open position, the cam profile causes a movement of the cam follower element and consequently of the said bearing portion so that the locking lever is automatically brought into its unlocking position.
In a particular embodiment, the inner portion of the mechanical linkage means is secured to a slider which is guided by a slideway inside a sealed compartment of the lock, along the opening travel of the mechanical linkage means, and which is capable, at the end of opening travel, of cooperating with a contactor for opening from the outside, to trigger the emission to an electric motor for assistance with opening of an opening control signal, which electric motor is capable of driving a lever for opening from the outside in order to actuate the pawl.
According to another feature of the invention, the said actuating lever is an emergency opening lever, for use in the event of an electrical failure or in the event of the vehicle battery being flat, capable of being moved by the linkage means under the action of the means for operating from the outside, over an additional travel beyond the opening travel needed to actuate the contactor, the said emergency lever being capable, during the said additional travel, of moving the lever for opening from the outside, so as to release the latch.
Advantageously, the emergency lever is subject to the action of a very stiff spring which returns it to its position of rest, which means that the user has to force the means for operating from the outside in order to actuate the emergency lever, so that the user will not needlessly actuate the emergency lever when electrical assistance with opening is working.
In a particular embodiment, the locking mechanism comprises a reversible electric motor for driving the locking lever between its locked and unlocked positions.
The four subjects of the invention may be taken alone or in combination with each other.